Oil burner control



April 6, 1937.

P. s. ARNOLD QIL BURNER CONTROL Filed May 15, 1936 ffz,

INVENTOR.

A TTORNEY.

Patented Apr. 6, 1937 UNITED STATES PATENT OFFICE 6 Claims.

This invention relates to oil burner controls and the object of theinvention is to provide a pneumatic control for use in connection with acompressed air operated oil burner which is started by closing allescape passages and allowing pressure to beibuilt up in the system by aconstant output air pump and stopped by opening an escape passage andallowing the pressure to drop.

Another object of the invention is to provide a thermostat arranged tooperate a mechanism whereby the air passages may be controlled so thatwhen the air passages are opened the pressure is allowed to drop to shutofi the burner and when the air passages are closed the pressure isallowed to'build up to start the burner.

A further object of the invention is to provide a device which isentirely automatic in operation as governed by the room temperature andrequires no manual re-setting.

Another object of the invention is to provide a lever which when turnedto one position will open the escape valve and when turned to the otherposition will close the escape valve, the movement of the lever beingcontrolled by the thermostat in combination with the air pressure of thesystem.

1 These objects and the several novel features of the invention arehereinafter more fully described and claimed and the preferred form ofconstruction by which these objects are attained is shown in theaccompanying drawing in which Fig. 1 shows the device in operatingposition with the pressure built up. Fig. 2 shows the device innon-operating posi- --::3 tion with the escape valve open.

Fig. 3 is an enlarged view taken on line 33 of Fig. 2.

The device comprises a casing I having vent apertures 2 shown in Figs. 1and 2. A circular 4 member 3 is secured to the bottom of the casing by"the bolt 4 and this member 3 is provided with an upwardly extending lug5 at one side to which the coiled thermostatic element 6 is secured. Atthe upper end this element 6 is secured to a mem- 45 her I which isconnected to a pinion 8 rotatably ll of the lugs [8 as shown in Fig. 3.

(Cl. 236-87) i A cylinder I9 is provided at one side of the casing l anda piston 23 is slidably mounted in the cylinder and is provided with anupwardly extending portion 2|. A coiled spring '22 is positioned aboutthe portion 2| and at one end engages against the top of the cylinderand at the opposite end engages against the piston 20.

This cylinder l9 at the bottom is provided with an air inlet opening 23through which air-may enter the cylinder from the air conduit 24. Theconduit 23 is provided with a vent aperture 25 which may be closed bythe valve 26 and when the valve 23 isopened the air may escape throughthe escape passage 21 into the interior of the casing l which is ventedto atmosphere by the apertures 2.

A rod 28 is connected to the piston in the cylinder l9 and extendsthrough the top of the cyl-. inder. This rod 28 extends through a guidebracket 29 and is provided with collars 30 and 3| secured to the upperend thereof. A lever 32 is pivotally, mounted at 33 on the bracket 34and the end of this lever is slotted or provided with anelongatedaperture through which the rod 28 extends. The lever 32 beneaththe pivot 33 is provided with an inturned foot 35 and this foot isarranged to engage the pawls 36 or 31 when the lever 32 is turned to thetwo positions shown in Figs. 1 and 2. A spring 38 is connected to theend of lever 32 and to abracket 39 and thisspring tends to pull thislever 32 to a neutral position. The pawls 36 and 3! are each providedwith a notch in the end thereofadapted to engage over the upturned lugsat the opposite ends of the member l2. The rod 28 is provided with acollar 43 thereon having an extending arm provided with-a pin 4| ridingin the slot 42 of a pivoted arm 43 which is pivotally connected to thebracket 44. Intermediate the ends of the arm 43 is a link 45 which ispivotally connected thereto and at the lower end is pivotally connectedto a bracket 43 having a spring 5| therein. The valve release lever 47is pivotally mounted on a bracket 48 and is pivotally connected to thelink 49 which in turn is connected to the valve 26.

In the position shown in Fig. 1 the valve 2'5 closes the escape aperture25 so that the air passing into the cylinder has raised the piston untilthe portion 2| has engaged the top of the cylinder. In Fig. 1 the partsare in position assumed during operation of the burner. As thetemperature of the room rises the thermostatic element 6 turns the gear8 in a clockwise direction, viewed from the top, thus moving the rack Hito the right of Fig. 1 and turning the member l2 on the pivot l3 toraise the right end of said member. This raises the fiat spring memberl6 above the upper end of the lever 41 and the spring through thebracket 46 turns this lever to the left of Fig. l to open the valve 26as shown in 5 Fig. 2. As the end of the member I5 is raised above theend of the lever 41, this lever 41 may move between the ends l1 of thelugs 18 shown in Fig. 3 and to the left of Fig. 1 until the end of thelever engages beneath the flat spring end 10 I5 which will be raised bythe end of the lever until the lever passes out from under the flatspring end l5, at which time, it will engage against said flat springend l5 as shown in Fig. 2. The opening of the valve 25 allows the airpressure to escape through the apertures 25 and 21 and as the airpressure is reduced in the cylinder IS the spring 22 forces the pistondownwardly. This downward movement of the piston lowers the collar 40and arm 43 and the link 45 turns the bracket 4'5 to the position shownin Fig. 2 thus placing a tension on the lever 41 and tending to move itto the right of Fig. 2.

However, this lever cannot move to the right due to its engagementagainst the end of the 25 spring trigger l5. Also during downwardmovement of the rod 28 the collar 3| engages the end of the lever 32 andturns it on the pivot 33 until the shoe 35 lifts the pawl 35 to theposition shown in Fig. 2. The control mechanism is then in position forsubsequent operation with the burner shut off.

As the room cools down, the gear 8 is rotated in a counter-clockwisedirection by the thermostat thus moving the rack Ill to the left of Fig.2 which raises the left end of the member l2 until the member I5 islifted above the upper end of the lever 41. At this time the spring 5|acting through the bracket 46 turns the lever 41 to the right of Fig. 2so that the upper end thereof passes under the fiat spring 16 to theposition shown in Fig. 1. This movement of the lever 41 closes the valve26 so that the air pressure passes through the passageway 23 into thecylinder I9 and raises the piston 20 to the position shown in Fig. 1against the tension of the spring 22. During this movement, the collar40 is raised to raise the lever 43 and link 45 to place a tension on thelever 41 to throw it to the left of Fig. 1. Also, the collar 30 inmoving upwardly moves the shoe 35 so that the notch in the pawl 36 mayengage the left end of the member l2 and as the piston reaches the topof its stroke the shoe 35 lifts the pawl 31 off from the right hand endof the member l2 so that the control is again ready for anotheroperation. The pawls 36 and 31 prevent" the trigger member 12 fromreleasing the lever 41 until the spring 5| has been given tension enoughso that it will force the lever 41 through its entire stroke whenreleased.

The temperature at which the thermostat will operate may be varied byloosening the nut 52 on the bolt 4 and turning the disc 3 to vary theposition of the lug 5 radially about the bolt 4. By this adjustment thethermostat may be set to operate the control at the desired temperature.Though not here shown, the conduit 24 is supplied with air underpressure by a constant output air pump which maintains a continuous airsupply.

From the foregoing description it becomes evident that the device isvery simple and efficient in operation, will automatically control anoil burner by opening or closing the air escape, may be adjusted forvarious temperatures and provides a device which accomplishes theobjects described.

Having thus fully described my invention, its utility and mode ofoperation, what I claim and desire to secure by Letters Patent of theUnited States is 1. An oil burner control comprising a perforatedcasing, a cylinder mounted in the casing, an air conduit opening intothe bottom of the cylinder, a vent valve for the air conduit, a leverpivotally mounted in the casing and turnable to one position to closethe vent valve and. turnable to another position to open the vent valve,a trigger pivotally mounted adjacent the free end of the lever andturnable on its pivot to move one end or the other of the trigger intothe path of travel of the lever, a thermostat connected to turn thetrigger on its pivot, a piston movable upwardly in the cylinder by airpressure, a spring tending to move the piston downwardly in thecylinder, means connected to the piston for applying pressure to turnthe lever in one direction as the piston moves upwardly, said meansbeing arranged for applying pressure to turn the lever in the otherdirection as the piston is moved downwardly in the cylinder, a pair ofpawls-pivotally mounted in the casing and arranged to engage the ends ofthe trigger to prevent movement of the trigger on its pivot and meansconnected to the piston for raising one pawl as the piston reaches thetop of its stroke and for raising the other pawl as the pistonreachesthe bottom of its stroke.

2. An oil burner control comprising a perforated casing, a cylindermounted in the casing, an air conduit opening into the bottom of thecylinder, a vent valve for the air conduit, a lever pivotally mounted inthe casing and turnable to one position to close the vent valve andturnable to another position to open the vent valve, atrigger pivotallymounted adjacent the free end of the lever and turnable on its pivot tomove one end or the other of the trigger into the path of travel of thelever, a thermostat connected to turn the trigger on its pivot, a pistonmovable upwardly in the cylinder by air pressure, a spring tending tomove the piston downwardly in the cylinder, means connected to thepiston for ap plying pressure to turn the lever in one direction as thepiston moves upwardly, said means being arranged for applying pressureto turn the lever in the other direction as the piston is moveddownwardly in the cylinder.

3. An oil burner control comprising a perforated casing, a thermostatwithin the casing, a pinion turnable by the thermostat, a rack meshingwith the pinion, a pivoted trigger movable by the rack, a cylinder inthe casing, an air inlet into the cylinder, an air vent for theairinlet, a valve for closing the air vent, a pivoted lever arranged inone position to close the valve and in the opposite position to open thevalve, said lever normally engaging one end or the other of the pivotedtrigger, spring means for turning the lever on its pivot, a pistonslidably mounted in the cylinder and movable upwardly by air pressurewithin the cylinder, a spring tending to move the piston downwardly andmeans operated by the piston for applying pressure to said lever on oneside or the other of its pivot;

4. An oil burner control comprising a perforated casing, a cylindermounted in the casing, an air conduit opening into the bottom of thecylinder, a vent valve for the air conduit, a lever pivotally mounted inthe casing and turnable to one position to close the vent valve andturnable to another position to open the vent valve, a trigger pivotallymounted adjacent the free end of.

the lever and turnable on its pivot to move one end or the other of thetrigger into the path of travel of the lever, a thermostat connected toturn the trigger on its pivot, a piston movable upwardly in the cylinderby air pressure, a spring tending to move the piston downwardly in thecylinder and means connected to the piston for applying pressure to thelever at one side or the other of its pivot.

5. An oil burner control comprising a perforated casing, a cylinder inthe casing, an air conduit opening into the bottom of the cylinder, avent valve for the air conduit, a lever pivotally mounted in the casingand turnable to one position to close the vent valve and turnable toanother position to open the vent valve, a trigger pivotally mountedadjacent the free end of the lever and turnable on its pivot to move oneend or the other of the trigger into the path of travel of the 20 lever,a thermostat connected to turn the trigger on its pivot, spring meansfor turning the lever in either direction, a piston in the cylinder andmeans connected to the piston to control the application of the springmeans to move the lever in one direction or the other.

6. An oil burner control comprising a perforated casing, an air conduit,a vent valve for the air conduit, a lever pivotally mounted inthe'casing and turnable to one position to close the vent valve and toanother position to open the vent valve, spring means arranged forturning the lever on its pivot, a trigger pivotally mounted adjacent oneend of the lever and turnable on its pivot to move one end or the otherof the trigger into path of travel of the lever, a thermostat connectedto turn the trigger on its pivot, spring means applicable to the leveron one side or the other of its pivot to turn the same in one directionor the other and pneumatically operated means for controlling theapplication of the spring means to the lever.

PHILIP S. ARNOLD.

